Pete's Log: vlsi fun
Entry #1168, (Coding, Hacking, & CS stuff)(posted when I was 23 years old.)
So I'm playing around with some VLSI stuff. I figured out today how to run mentor graphics remotely, which means I can play with it from my office without having to go downstairs. Mentor actually makes life pretty easy in this regard, it comes with a shellscript called
mgc_font_collect that copies all the mentor fonts installed into a specified directory. All you need to do then is copy the fonts in that directory to your local system, add them to your font path, and mentor runs remotely like a champ. Well, almost. There's a small issue with it not liking to refresh the screen automatically if the window was hidden, but it's easy to force a refresh, so that's no big deal.
So we were given a few basic cells to use in our project so that we didn't have to design them ourselves. Among other things we were given inverters, adders, and flipflops. Well, I'm becoming somewhat frustrated with the cells we were given. The first issue, which really isn't a problem at all, is that the cells use metal 2, and one of the fab processes we're targeting doesn't support metal 2, so the cells need to be hacked up a bit to get rid of all the metal 2. The second issue is that the cells don't pass ic layout rule checks. The flipflop cell, I think, had 30 some errors. Granted, I have little clue as to what I'm doing, so it may turn out that I'm not using the proper rule file or something, but I think I'm doing things right... so I'm fixing all the errors and in the process I'm both figuring out how IC Station works and how the cells we were given work. I'm curious to see if fixing these errors will prove to have been unnecessary ...